The Navigator is SUPPOSED to serve as a MAP of the document. But it has a major
limitation: A map is useful only if you know your current location in the map.
But the Navigator does not tell you where you are at present. 

Compare this with the "Style and Formatting" window, which always highlights the
current style. Likewise, the Navigator must highlight the current item (i.e.,
table, heading, figure, frame, etc.)

Note that the user can make sense of only the "Heading" entries in the
Navigator, because he can read the actual text of the headings in the Navigator
box. But all other items (e.g. Tables) are identified by number, which makes no
sense to him. So he can't use the Navigator alone to identify which table he
wants to jump to.

For example, suppose your document has  a lot of tables and it is your intention
is to navigate through these tables. In that case, the Navigator will show a
long list of tables, but will not tell you which table you are at. The only way
you can identify your current table is to look up its number from the status
line; and then to look up that number in the Navigator's "Tables" list. 

Locating a table number in the Navigator is not easy, because the list is not in
ascending order; and many numbers may be missing (if you had deleted some tables
in the document). Worse, you cannot renumber the tables.

The same problem also applies to all other items (e.g. images).

So, like the "Styles and Formatting" window, synchronize the Navigator also with
the document.